Turn to the right (west) and go through the pathway through the wall. To avoid the aggro jungle khvara at the other end of the pathway, keep to the left of the pathway and turn left immediately at the other end of the pathway ( 1896, 114, -368 ) /waypoint 1896, 114, -368.

Follow the river to the left (south) from the entrance, to an aqueduct at ( 1871, 114, -301 ) /waypoint 1871, 114, -301.

At the edge, below you, is a vine. Walk (drop) to the vine and follow it to a broken piece of a bridge on the other side at ( 1867, 114, -192 ) /waypoint 1867, 114, -192.

Walk this platform to its edge, dropping down again to the platform below it at ( 1873, 96, -141 ) /waypoint 1873, 96, -141. This is where Grugla is. From here, you can take another vine to get down safely. (Alternatively, you can try jumping down to the water).